This study examines whether or not Japanese speaking learners of English as a foreign language (EFL) understand referents of null subjects in infinitives, based on experimental results we obtained during the investigation of L2 acquisition of the control and seem raising constructions. In particular, it is revealed that the acquisition of PRO and A-movement is influenced by intervention and L1 transfer effects. By examining these constructions, we wish to deepen our understanding of null subjects in Japanese EFL learners' interlanguage grammars.

This study investigates how sensitive elementary/pre-intermediate-level Japanese-speaking learners of English (JLEs) are to the ungrammaticality of sentences involving illicit subject drop. In an effort to elicit JLEs' implicit linguistic knowledge of illicit subject drop, the experiments conducted in this study adopted the self-paced reading task, which is considered to reduce interference of explicit linguistic knowledge. The results show a trend for JLEs' sensitivity to illicit subject drop, supporting the view that even JLEs, whose native language exhibits topic-prominence, can reset a parameter to the subject-prominence value.

In this study, we examined the phonological processing performed by Chinese learners of Japanese (CLJs) in Japanese kanji recognition. In particular, we examined whether CLJs perform non-articulatory control processes that native speakers of Japanese perform. In Experiment 1, 17 advanced-level CLJs performed a homophone judgment task of Japanese two-word kanji pairs. The results showed that under the articulatory suppression condition, there were more errors under the homophone-pair condition than the control-pair condition, suggesting that CLJs performed an articulatory control process in phonological processing. In Experiment 2, we divided 40 CJLs into fast and slow groups by Japanese phoneme conversion speed. An experiment similar to Experiment 1 was performed, and the stimuli were revised for Chinese Japanese learners. As a result, errors also increased under articulatory suppression. In addition, the response time showed that learners with faster phoneme conversion speeds were more susceptible to articulatory suppression, suggesting that unlike native speakers of Japanese, CJLs separate the articulation of Japanese kanji into finer units whereby it is easier to perform articulatory control processes, and CJLs with a faster phonological conversion speed may find it easier to do so.